The above referenced co-pending applications discuss controlling the fluorine injection into separate chambers of a multi-chambered excimer or molecular fluorine gas discharge laser system separately for each chamber and to use signals representative of voltage applied to one or both chambers, the energy output of an oscillator chamber and bandwidth as part of some control function. However, as useful as these systems are, improvements are needed to better utilize laser system parameters that relate to fluorine consumption to perform such control and the present application deals with these improvements.